When data sensed through sensor networks are used, an application program must directly process and integrate the sensed data in order to provide information to a user using a specific sensor network. This way requires a lot of manpower and is cost-consuming. In addition, as the number and kinds of sensor networks required for generating an information service increase, the application program must be modified and enlarged to meet a processing capability requirement with respect to a communication scheme, control protocol, functional features, and sensed data processing scheme of each sensor network. Furthermore, when the sensed data collected from the same sensor network is simultaneously used in one or more application programs, the control and communication cost of gateways and sensor networks increases, resulting in performance degradation of the sensor networks and reduction of power resources.
In Ubiquitous Sensor Network (USN) environment, a plurality of sensor networks having different purposes and functions are expected to be installed or distributed in a wide area. Sensor nodes of each sensor network collect environment information in real-time while they are attached to objects, placed in a position, or in motion.
In order for the application program to provide useful information service to the user, there is a need for a means that can abstract one or more heterogeneous sensor networks, generate events and context aware information by analyzing sensed data from a corresponding sensor network, and provide the generated information to the application rapidly and conveniently. However, such a means does not exist at present.